Portable chair



FIG. 1 is a top, front, right perspective view of a portable chair showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines immediately adjacent to the shaded area define the bounds of the claimed design and form no part thereof. The broken lines depicting the remainder of the portable chair form no part of the claimed design. 

CLAIM The ornamental design for a portable chair, as shown and described. 